Tuesday, October 14, 2014

Reducing uncertainty and Jasper Kirkby of CERN's CLOUD

At WUWT, I saw that there is a new TED-Ed video by a particle physicist at CERN. As you probably know, a team at CERN is investigating the details of how clouds form, as part of a project called "CLOUD".

A fair bit of the video is just basic climate science. I have to say, though, that Jasper Kirkby seems prone to self-aggrandisement, big-noting his research and implying that his experiment is going to pin down a precise number for climate sensitivity.

He's also a bit misleading. Jasper Kirkby said:

"When concentrations of carbon dioxide in the atmosphere double, which is expected before the end of the 21st Century, researchers project that global temperatures will have risen by 1.5C to 4.5C. If the increase is near the low end, 1.5C, then we're already half way there, and we should be more able to adapt with some regions becoming drier and less productive but others becoming warmer wetter and more productive. On the other hand, a rise of 4.5C would be similar in magnitude to the warming that's occurred since the last glacial maximum, 22,000 years ago, when most of North America was under an ice sheet two kilometres thick. So that would represent a dramatic change of climate."

In fact:

At present rates of emissions, the concentration of CO2 in the atmosphere is likely to double about half way through this century, well before the end of the century.

We are not yet halfway to a doubling of CO2. CO2 has risen by 120 ppm of the 280 ppm extra required to double atmospheric CO2, which means we are 43% of the "way there".

Earth's temperature will not stop rising after CO2 doubles.

There is more that I find fault with in his short video. He claims that "it is vitally important for scientists to predict the change in temperature with as much precision as possible so that society can plan for the future". He implies that it's only global average surface temperature that's important. Sure it will help, but just as important is planning for sea level rise, planning for ocean acidification and figuring out what changes there will be at the regional level.

Jasper claims that the "present range of uncertainty is simply too large to be confident of how best to respond". I disagree. We already know enough that at the very least, we need to cut emissions of CO2. We need to switch away from burning fossil fuels and move to renewable energy sources.

Then Jasper Kirkby implies that his experiment is what the climate science world, maybe the entire world, has been waiting for. He claims that the range of climate sensitivity is all down to uncertainty in clouds and aerosols. He said:

"But this estimate of 1.5C to 4.5C for a doubling of carbon dioxide hasn't changed in 35 years. Why haven't we been able to narrow it down? The answer is that we don't yet understand aerosols and clouds well enough. But a new experiment at CERN is tackling the problem."

Although the IPCC AR4 report stated in one section that "...cloud feedbacks remain the largest source of uncertainty in climate sensitivity estimates", they are not the only source. There are other things that impact climate sensitivity, like how quickly the ice will melt and affect the amount of sunlight reflected vs absorbed. Like what can we learn from past climates. Like what will happen to ocean circulation and ocean currents as we heat up the planet. It's not just clouds and aerosols.

Jasper then goes into a short explanation of climate sensitivity and radiation imbalance, which is fairly straightforward. He goes on to talk about the increase in greenhouse gases and the increase in aerosol particles. But he refers to them as "But our activities have, at the same time, increased the amount of aerosol particles in clouds, which have cooled the planet." I might have misunderstood what he's trying to say. It looks as if he is mixing up two notions. Some clouds have a warming and some have a cooling effect. And aerosol particles don't just end up in clouds. AFAIK they can reflect sunlight (not all aerosol particles do this) in their own right, whether in clouds or not.

Jasper goes into a spiel on clouds, saying, quite rightly, that we have no way of knowing how cloudy it was in 1750. Jasper Kirkby makes much of the fact that this is arguably the main source of uncertainty, which is probably true, in climate feedbacks at least. However as noted earlier, it's probably only part of the picture. It seems to me that Jasper Kirkby is wanting to inflate the importance of his CLOUD experiments. The work of CLOUD should help in understanding what happens at the micro level. There is also a lot of work being done at the observational and macro level, such as NASA's CERES.

The CLOUD experiments will no doubt be of considerable value once they starts generating more results. But to suggest that his team and his team alone is going to unravel all the mysteries of climate change is going a mite too far, surely.

Jasper Kirkby explains the different types of atmospheric aerosols - as primary or secondary etc. He describes how a cloud cannot form without an aerosol particle seed. He explains, also quite rightly, that the way aerosol particles contribute to cloud formation is poorly understood, for various reasons. But he goes back to claiming that it's the uncertainty of aerosol/cloud formation that is "the primary reason for uncertainty in climate sensitivity and the corresponding wide range in future climate projections". That seems like a generalisation, or should I say, it's too specific. He could be correct, but I don't know that it's just the aerosol/cloud part that's the primary reason for uncertainty. (He keeps repeating this as if people might not register the importance of clouds to weather.)

Jasper says how he and his colleagues at CERN have "managed to build a steel vessel that's large enough and has low enough contamination that aerosol formation can, for the first time, be measured under tightly controlled atmospheric conditions in the laboratory."

He says that "in its first five years of operation, CLOUD has identified the vapours responsible for aerosol formation in the atmosphere, which include sulphuric acid, ammonia, amines, and biogenic vapours from trees." I believe that a lot of people knew that already, before CLOUD. What CLOUD can contribute is more details of the reactions that take place.

Jasper also says that "CLOUD is also investigating if galactic cosmic rays enhance the formation of aerosols in clouds. This has been suggested as a possible unaccounted natural climate forcing agent, since the flux of cosmic rays raining down on the atmosphere varies with solar activity." Thankfully, as will be seen below, he doesn't try to claim that cosmic rays have anything to do with this period of climate warming.

Jasper sums up by telling us how CLOUD is addressing two big questions:

Firstly, "how cloudy was the pre-industrial climate and hence, how much have clouds changed due to human activities." Jasper says, "that knowledge will help sharpen climate projections in the twenty first century".

Secondly, "could the puzzling observations of solar climate variability in the pre-industrial climate be explained by an influence of galactic cosmic rays on clouds".

I applaud the work of the CLOUD team. I'm not trying to downplay its importance. However it strikes me that Jasper Kirkby is big-noting himself just a tad. I don't see that his work and that of his team on the CLOUD project is the saviour of climate science and the world at large, as he seems to think.

I've included the video below. It looks as if Jasper hasn't answered his two questions yet, though I gather they are helping scientists understand better the micro-physics of clouds, which will be very useful knowledge.

He doesn't need to grandstand.

If you think I've been too harsh with Jasper Kirkby, let me know in the comments.

From the WUWT comments

As I said, Anthony Watts posted the video at WUWT. Here are some of the comments.

DonM is complaining that the video presented global warming as a fact. He also talks about precision vs accuracy:

October 13, 2014 at 3:05 pm
That’s exactly what first jumped out at me as well (but the video narrative does not say predict the RISE, or increase; although the video narrative does say “…predict the change…”).

The second thing that jumped out was that they think that they need to predict the change with better PRECISION. I don’t care how precise they are … if the predictions are not ACCURATE then the level of precision is worthless. They can miss the predicted target, by a consistent 4 degrees (high) in twenty different manipulated models, and then tout how precise the modeling is, but it still will not prove to be accurate.

Some terms are not interchangeable. Some terms are only interchangeable in proper context. Using the terms in the wrong context is either a show of ignorance … or worse.

Rud Istvan is mistaken. The only claims that were dismissed out of hand were claims that modern warming isn't from greenhouse gases but from cosmic rays. No scientist that I know of dismissed out of hand any claim that galactic cosmic rays might affect cloud formation. Though they obviously aren't a major influence.

October 13, 2014 at 12:28 pm
Actually, I find this hopeful. Previously, Svensmarks hypothesis was being dismissed out of hand. Now, there is serious experimwntation at CERN showing the hypothesis has some merit. Further unsettling the previously ‘settled science, and further unsettling the ‘debate is over’ crowd like Kerry and OBama. The more the general public understands it isn’t settled, the more the political wind goes out of their sails.

BTW thanks to AW to todays WUWT ad on my last book, intentional or not a nice shout out.

This comment from Bill_W sounds a bit like the comment from Anthony Watts about the Berkeley Earth exercise, until he changed his tune when it found the same as every other temperature reconstruction.

October 13, 2014 at 4:44 pm
Now that CERN is doing the experiments with dozens of scientists from around the world (if it is anything like every other CERN experiment) it will be much easier to publish and discuss without repercussions.

You can’t very well say that it’s not physics when it’s done at CERN. And if it has a lot of authors, it is hard to call them deniers. Especially if you don’t want a thousand other physicists to suddenly wake up and jump down your throat. Even if it starts to warm again at 0.15 C/decade, it will be hard to keep up the really wacko alarmist crap.

DHR

October 13, 2014 at 1:32 pm
The pitch assumes that the temperature increase from 1750 is due to CO2 increases. That is a grand leap of faith. Faith is a poor substitute for facts. Are any unfaithful scientists working on the CLOUD program?

October 13, 2014 at 11:07 pm
Thanks. Their cloud chamber conditions include ultra clean air and temperature stable to 0.1 C. Nothing like the real atmosphere. They may discover interesting physics but may not be what’s happening in the atmosphere. They should also simulate dirty air and highly varying temperature.

Note: In the original version I inadvertently referred to Jasper Kirkby as James Kirby. Goodness knows why. Thanks to anonymous for correcting me. Sou 14 October 2014.

>"We are not yet halfway to a doubling of CO2. CO2 has risen by 120 ppm of the 280 ppm extra required to double atmospheric CO2, which means we are 43% of the "way there"."

..which, using the standard radiative forcing formula makes the sensitivity to CO2 at the lower end of the IPCC range. (Even before we account for AMO and lower clouds ... which will lower it still further ;-P )

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

dT = sensitivity x forcing dT = (lambda) x (5.35 x ln(C1/C0))

CO2 has risen from 280 to 400 ppm. Temperature has risen 0.8C. Solve for lambda.

No. You've assumed that 0.8 is the final temperature rise after CO2 is 43% greater than it was before industrialisation. That's where the "transient" comes in. The air would continue to heat up even if we kept CO2 constant at 400 ppm (ie cut emissions by probably around 70% immediately.)

If we kept CO2 at the same level (400 ppm) the heat in the oceans would continue to warm the atmosphere for starters. You've not allowed for all the feedbacks to catch up.

TCR for 400ppm CO2 is ~0.8C (observed) with ~0.6C in the pipeline (estimated assuming ECS is ~3C), giving an equilibrium response to 400ppm CO2 of ~1.5C. All uncontroversial, standard stuff if we assume an ECS / 2 x CO2 of ~3C.

RR has worked out the equilibrium response to 400ppm CO2 (~1.5C). All I did was check RR's calculations using 3C as the explicit value for ECS. As expected, he has shown (but not understood) that ECS / 2 x CO2 = 3C.

RR implicitly assumed we're at equilibrium and found 1.55C ECS. His math works out fine. But we aren't at equilibrium; he actually calculated an estimate to the TCR.

He said that T1-T0 = k ln(C1/C0). Throw in the values for today (dT = 0.8C, C1=400, C0=280) and calculate k. Next, take that k and throw in C1=2C0 to get an estimate to the TCR. That's all that RR did. His 1.55C is for a doubling of CO2, which is why there's a ln(2) term in there.

Your calculation is finding that 3C ECS is not consistent with assuming that we're at equilibrium now, because we've only warmed about half as much as expected. So either 3C is wrong (which is RR's contention) or equilibrium is wrong (which is mine and Sou's).

I hope you are having a pleasant evening. I must say you are great. That was hilarious!

dT = 3ln(560/280)/ln(2) = 3C

That'll get 'em every-time!

For those that don't get BBD's joke: ln(560/280) is exactly the same thing as ln(2). So to get the result of dT of being 3 he's just written:

dT = 3

(As the ln(2)'s just cancel)

What you've messed up on me old china is to get ECS from this approach you need to multiply the forcing by the sensitivity. The sensitivity in this case is NOT the ECS! It's the term to say how many Wm^-2 are converted into degrees C. Units for it are K/(W/m2). Values for it are always an estimate. The IPCC likes to use values around 0.8. (= 3C). This is their guess. But as we've seen - and you seem to agree with - that we can calculate it from the instrumental record, and it comes out half the IPCC's value

The other factor, the radiative forcing, is most often expressed as 5.35 x ln(C1/C0) for CO2

If you have trouble with this stuff can I recommend you try Wiki, SKS, The IPCC, or RC, or even WUWT!

What you've messed up on me old china is to get ECS from this approach you need to multiply the forcing by the sensitivity.

I wasn't estimating sensitivity as you were. I was calculating dT for a *specific value* for ECS.

For those that don't get BBD's joke: ln(560/280) is exactly the same thing as ln(2). So to get the result of dT of being 3 he's just written:

dT = 3

As you would expect when ECS=3 for 2xCO2. Are you taking the piss?

Let's calculate dT for 800ppm CO2 under the assumption that ECS = 3C:

dT = 3ln(800/280)/ln(2) = 4.5C

* * *

Now what *you* did was the old Lindzen trick - and it is a trick, let's make no mistake about that - of ignoring ocean thermal inertia and negative aerosol forcings. You take observed temperature change of 0.8C as if it represented the full, unmediated effect of dF but of course it doesn't. Hence your (deliberate?) underestimate of ECS.

I thought you were just an incompetent who would not admit error. Now I'm beginning to wonder if you are doing this on purpose.

RR wrote "The IPCC likes to use values around 0.8. (= 3C). This is their guess. But as we've seen - and you seem to agree with - that we can calculate it from the instrumental record, and it comes out half the IPCC's value"

For a start, the value of lambda at 0.8C is NOT a guess, but calculated from paleoclimate data, where the climate was forced, and then allowed to reach equilibrium before the temperature was used in the calculation.

The reason why you are getting the wrong value from using the instrumental record is that the earth hasn't reached equilibrium yet. You CANNOT solve for lambda using the short instrumental record until the earth has been given time to equilibrate. That is where the E in ECS comes from. It stands for equilibrium, You also seem to think, erroneously I might add, that BBD agrees with you. He doesn't. He is trying to point out where you have gone wrong, but you blithely ignore him.

Look, this is really basic stuff, yet you still mange to completely stuff it up. Is there something about the word equilibrium that you don't understand? You do understand that the earth is NOT at equilibrium at the moment and so your calculations are utterly bogus?

The 3 in your term is 3C? Is that what you are taking the sensitivity (note: which is different to ECS..) as? If so the units are wrong! The term for sensitivity in these equations is in the units "k per watts per sq metre". The ECS is simply in C (or K).

So what the BBD equation is saying (I presume the Nobel committee won't be disappointed and that you claim credit for your new equation? If not you'd better fess up as withdrawing the prize after you've won it may be embarrassing for them) is that the forcing in W/m2 for a doubling of CO2 is much less than previously supposed by climate science:

We know that the ECS is the forcing times the climate's sensitivity to that forcing, or... in maths (I've put the units in brackets)...

dT (in C) = sensitivity (lambda, in C per W/m2) x forcing (in W/m2)

I've put the units in brackets.. but from the BBD equation we have the actual numbers...

dT = 3 x ln(560/280)/ln(2)

So the forcing term (in Watts per square metre) is, in your equation, ln(560/280)/ln(2). Is that correct? If it's not correct what is the forcing term in the BBD equation?

If so, congratulations Agent Koch, your denier work is done. Return to base to collect your Iron Cross. You've just shown (nay, proved!) that the forcing of CO2 is only 1 W/m2. Those IPCC folk (how they must cower at your brilliance) say it's 3.7 W/m2. But, pah! They know nothing compared to you. Let them chew on this...

ln(560/280)/ln(2) = ln(2)/ln(2) = 1 W/m2

>"Now what *you* did was the old Lindzen trick - and it is a trick, let's make no mistake about that"

There's no "trick". The ECS really *is* the sensitivity x forcing. Read that wiki article. You seem to be (or is it a double bluff, Agent Koch ;-)) confused about the terms sensitivty (in K per W/m2) and ECS (in C). They are different!

RR - I can't make head or tail of what you are trying to say. You are saying that sensitivity = sensitivity x forcing? Really? (And you talk about matching units!)

Equilibrium climate sensitivity is the climate sensitivity at equilibrium. It is the change in temperature after a doubling of the forcing, after feedbacks have come into play and the system has settled down - (though in much of the literature, it's before the very long term changes have completed).

It isn't climate sensitivity at equilibrium multiplied by anything. Climate sensitivity isn't climate sensitivity multiplied by forcing. It is just climate sensitivity. It is measured in degrees Celsius (or Kelvin if you prefer).

I am not making stuff up here! It's Agent Koch (aka BBD) who is the misinformation agent - and he's bloody brilliant!

>"For a start, the value of lambda at 0.8C is NOT a guess"

From wiki:

"addition of these feedbacks leads to a value of the sensitivity to CO2 doubling of approximately 3 °C ± 1.5 °C, which corresponds to a value of λ of 0.8 K/(W/m2)."

lambda is in K/(W/m2) NOT C! Note that they estimate lambda FROM the forcings and temperature response. They don't take lambda and calculate the radiative properties of CO2, because that's known from laboratory experiments. So lambda technically is a "first order approximation" and how exactly is that different from an (informed) guess..?

>"calculated from paleoclimate data, where the climate was forced, and then allowed to reach equilibrium before the temperature was used in the calculation."

Yes, it was calculated from (highly selected) paleoclimate data. But the rest of your sentence does not make sense. "Allowed to reach equilibrium"! When was that exactly? What dates was the climate in equilibrium? What years? 1034? 1126? You can never tell, from Paleoclimate data alone, when the climate is in equilibrium. You can't tell history "I'm allowing you back into equilibrium".

That's why computer models are used, as with those you can set the tunable parameters (at least 11 guesses more..!) to get a result, that following the tunable parameters is ultimately a guess, or I should say a "first order approximation".

And back in the real world the world has NEVER been in equilibrium! The temperature is always going up and down. It's a highly non-linear, high stochastic problem with probably hundreds of functioning parameters, whose values are interdependent and can never be simultaneously known!

In short: It's a headscratcher. That's why I think, as I said to SOU above, that ECS, or the whole notion of the climate's sensitivity to only one of the hundreds of inputs is a farce. The intention was to show that even with the standard equations results are wrong. Now we have the bizarre situation that I'm trying to defend climate science's methodology - and you, Sou and Agent Koch are trying to attack it!

"The reason why you are getting the wrong value from using the instrumental record is that the earth hasn't reached equilibrium yet. You CANNOT solve for lambda using the short instrumental record until the earth has been given time to equilibrate. "

1) The value is not wrong. If you think my values are incorrect just show me - with maths.

2) I did not invent this equation. I haven't got BBD's amazing "brilliance". The equation for ECS is a standard climate science (tm) equation. It is dT = lambda x forcing. It's a fact.

3) The value for lambda is where you can (theoretically) make assumptions (guesses) for the climate returning to equilibrium. The equation is valid. It's the heat balance approach to ECS. Look it up.

4) "You CANNOT solve for lambda using the short instrumental record". Yes you can. The fact that it comes out around half the paleo record is just one of those "inconvenient facts". And the instrumental record is centuries long.

>"Look, this is really basic stuff"

Yes. Yes it is. Can I recommend the wikipedia article as a starter for you?

There does seem to be some confusion here! The ECS, or TCS, or other measures are the final temperature response. Rather confusingly the lambda (as in here is also called sensitivity, but it's the explicit parameter of an energy balance model. It's how many degrees C will the climate respond to, to a radiative forcing of (e.g.) higher CO2.

So my equation is correct. What I've done is show that using the modern temperature record, the value for lambda, and thus ECS, is at the lower end of the IPCC range. It's really not controversial. I even read Michael Mann saying the same, but then going on to say why we can't trust those thermometers - tree-rings are much better..;-D

>"The bigger question is, where do you get your strange notions from?"

The 3 in your term is 3C? Is that what you are taking the sensitivity (note: which is different to ECS..) as? If so the units are wrong! The term for sensitivity in these equations is in the units "k per watts per sq metre". The ECS is simply in C (or K).

I am not doing this:

dT = λ*dF

You have failed to understand what is being shown. You will need to go back and read it again.

The 3 = 3C = ECS *not* sensitivity (k / W /m^2).

The calculation is for *dT* using a given value for ECS and varying values for CO2. It is not for ECS. It is not for sensitivity (k / W /m^2).

You used the Lindzen trick and got caught. End of story. See Sou, numerobis and DJ, above.

"We can look at the expected warming from various climate sensitivities [***] to determine the surface temperature rise expected from the enhanced [CO2]. For a climate sensitivity of 2oC (of surface warming per doubling of atmospheric [CO2]) this is around 0.85 oC at equilibrium (for a [CO2] increase from 286-386 ppm), and for a 3 oC sensitivity, ~1.25 oC of surface warming.

"Since we’ve already had 0.85 oC of warming without taking account the aerosol effect and the climate response time), it’s very unlikely that the climate sensitivity can be lower than 2 oC of warming per doubling of atmospheric CO2. A similar conclusion was recently obtained from an obviously (!) much more detailed analysis of the Earth’s energy balance since 1950 (Murphy et al. (2010).

"[***] delta T = (ln([CO2]final/[CO2]start))*s/ln(2)

where deltaT is the surface temperature change expected from a change in [CO2] from [CO2]start to [CO2]final in ppm, and s is the climate sensitivity in oC."

BBD, I forgot to put the '/(W/m2)' when I was talking about lambda. He was chastising me. I totally accept that I got the units wrong. Easy mistake.

Now, back to the question at hand. How do you calculate lambda, or S and it's also known.

As I was trying to say, but RR is still not listening, you cannot use the formula that RR provided, using the instrumental record. The formula is for the ECS, and cannot be used while the earth is still not in equilibrium. That is why paleoclimate data is much better, as it allows the time for the climate to equilibrate. (Yes, the climate is never at a true equilibrium, but for the purpose of the calculations, a variance of a few 0.1K's will suffice)

Now, as I said before, but it still hasn't sunk in, the value for lambda is calculated from paleoclimate data.

Here is an example.http://www.nature.com/nature/journal/v491/n7426/full/nature11574.html

Using NOT highly selected paleoclimate data, as RR would like to claim, but from paleoclimate data spanning 65 million years.

So using the past climate, they calculated lambda to be 0.6–1.3, with a mean at 0.8. So as you can see, the 0.8 figure is NOT a guess, but a calculation from the past climate

Now, using 0.8K/(W/m2) for lambda x 3.75 W/m2 for 2xCO2, you get a 2xCO2 ECS of 3K.

The reason for RR very low figure of lambda is that the earth hasn't had time to equilibrate to the forcing in the calculation. There is still warming 'in the pipeline' that wasn't accounted for by RR.

Ah! Thanks for the source of the "BBD" equation! Pity though. I thought he'd made it up himself! Although why would one use an equation from a comment in a blog post rather than the official literature...?

RR you are acting like the most ignorant of denier trolls. BBD is using accepted science (see my reference above, for example, if you can't figure it out for yourself.)

And make up your mind - is it a "standard equation" or "some random due [sic] in a four year old blog post"?

Read the comments from BBD and others again and try to understand them. If you can't (and you have shown no sign of doing so to date) then you've no business lecturing those who do understand what they are writing. Your errors have been pointed out by numerous people.

I've just about had enough of you clogging up the discussion with your pseudo-science crap. You show no willingness to learn from other commenters here who know about the subject. A bit of humility on your part would go a long way.

BBD's remarks in this thread are more than a little confusing. I would have written them differently. In fact, the first few comments from BBD are a real mess.

But Sou's initial response to RR ("You've taken a shot at calculating transient climate response (TCR), not equilibrium climate sensitivity") was exactly correct.

RR is producing a simplified estimate of something that could be called "transient climate sensitivity" and then applying that to the forcing from 2XC02 to estimate transient climate response (TCR).

Which is fine. What's not fine is that he/she claims that it's ECS. That claim is flat-out wrong, because RR is using transient temperature change per unit forcing rather than equilibrium temperature change per unit forcing.

No, it's not ECS. The system nowhere near equilibrium. As was pointed out at the outset, the system is not at equilibrium. Outgoing radiation is less than incoming. So you're using the wrong number with 0.8C.

RR - given you refuse to admit your errors after they've been pointed out by numerous people, I won't be accepting any more comments from you on the topic - unless and until you change your tune.

Aside from the problem of RR using transient dT to calculate equilibrium climate sensitivity ... the other problem is that the observed (transient) dT is the result of other forcings besides CO2.

If one wants to do this (RR's calculation) correctly, one has to include the effects of non-CO2 GHGs, as well as aerosols, solar, etc. Maybe ENSO and/or other representations of the state of the oceans, depending on what exactly you're trying to study. Yes, it's more complicated, and some of the factors are only poorly quantified. But the fact that the right way of doing something is hard doesn't make the easy way of doing it right.

BTW, about the reference to WUWT provided by Sang Som, where Jeff L. used the same equations as BBD. It is the same article that I referred to in my link way up high, when I first replied to RR's wrong calculation. RR made the same mistake as Jeff L. did at WUWT.

Agree, Ned W. I don't know why RR thinks it's all so easy. Especially when you think of all the various attempts by scientists and non-scientists alike, publishing their various papers on the subject.

Frankly, I'm happy enough with the range of 2C to 4.5C and I'd be surprised if ECS can be narrowed down much more than that after CO2 is doubled. Scientists might be able to narrow TCR a bit better but even that will be hard to pin down exactly after CO2 has doubled, because of natural internal variability.

And sorry for the link and the overlap with previous links. Just found it curious that RR initially thought BBD had made up the calculation...

Thing is, by simply picking dates and datasets, we could also "prove" that "ECS" is much higher. Like GISS 1970 - 2013 = 2.5. Or UAH 1992 - 2013 = 3! OMG. But we don't do that since (1) it's NOT really ECS and (2) it's pure cherry-picking. And that's not how science works.

This seems to be getting a little heated, which wasn't my intention. So sorry if I upset anybody with attempts at humour. Following Sou's posting of the Knutti and Hegerl paper I now accept that BBD's equation is a valid form of the same equation I was using, with ECS instead of lambda as the tunable parameter. I also repeat that I don't believe (nor does Hansen) that ECS is a valid climate metric anyway. I only did the calculation to show that the instrumental record data only supports the lower end of the IPCC range.

Is it the final word? Of course not! It's one line equation. But a common feature among studies that use instrumental data is that their sensitivity is MUCH lower than paleoclimate reconstructions. You can't brush that under the carpet or wish it away. They are peer-reviewed papers.

In the Knutti and Hegerl (thanks Sou) paper I see this:

"The beauty of this simple conceptual model of radiative forcing and climate sensitivity (equation (1)) is that the EQUILIBRIUM warming is proportional to the radiative forcing and is readily computed as a function of the current CO2 relative to the pre-industrial CO2:ΔT=Sln(CO2/CO2(t=1750))/ln2." [my caps, my bold]

So the figure is for ECS, calculated by the standard equation, or by that preferred by BBD and Knutti and Hegerl.

So again the equation is referred to as for ECS. Also see the wiki on radiative forcing:

"Radiative forcing can be used to estimate a subsequent change in EQUILIBRIUM surface temperature (ΔTs) arising from that radiative forcing via the equation:

dT=lambda x forcing" [again my caps]

Same again. Also see the IPCC definition of ECS:

"The equilibrium climate sensitivity is a measure of the climate system response to sustained radiative forcing. It is defined as the equilibrium global average surface warming following a doubling of CO2 concentration."

So, I think me saying the equation (of either form) is for ECS is understandable.

So he, along with all the other papers I linked to, thinks it's ECS. I was only using his equation. Remember that I don't think these equations are any good anyway, but you can't have a term in an equation and then say: "You can't solve for that!" It's very unscientific.

I'll close by repeating what I said to DJ:

"And back in the real world the world has NEVER been in equilibrium! The temperature is always going up and down. It's a highly non-linear, highly stochastic problem with probably hundreds of functioning parameters, whose values are interdependent and can never be simultaneously known!

In short: It's a headscratcher. That's why I think, as I said to SOU above, that ECS, or the whole notion of the climate's sensitivity to only one of the hundreds of inputs is a farce."

RR - you emphasized the word "equilibrium" in the quote from Knutti and Hegerl but you do not understand the meaning. Your value of 0.8C is *not* the equilibrium temperature, therefore it is not a valid number to use in that equation. At best, it is an attempt by you to estimate transient climate response.

In the equation ΔT = S ln(CO2/CO2(t=1750))/ln2, the ΔT = equilibrium temperature change, which is not the difference between T(now) and T(1750). It will be higher than that. (If we knew how much higher, then we'd know the value of ECS.)

The CO2 (now) and CO2 (1750) is fine, but the number you've plugged in for ΔT is incorrect. 0.8 is *not* the temperature difference at equilibrium. I'll repeat - the temperature difference at equilibrium would be higher for 400ppm.

I suggest you read the entire paper to get an understanding of the issues involved in trying to estimate equilibrium climate sensitivity.

I've only allowed your comment because a) you acknowledged that the equation is valid and b) it would appear that you genuinely do not understand the meaning of the word "equilibrium" in the context of equilibrium climate sensitivity. It means when outgoing radiation = incoming radiation. It would mean, if CO2 stabilised at 400 ppm, the final temperature reached - which would be more than 0.8C above that in 1750.

Go away and think on it more. Do more reading if you really want to understand the situation.

BBD - it appears that RR genuinely does not understand the concept of ECS or even what the word "equilibrium" means. Even after looking at the Knutti and Hergel paper, which if he didn't "get it" by reading all the responses to his comments here, he should have understood it from Knutti and Hergel.

He's suffering a mental block, which is not an uncommon trait in people who cannot accept climate science.

I don't think there is any point in trying to bash it into his brain. Either he'll figure it out sooner or later or he won't. There's not any more that we can do to help IMO.

BTW I thought RR's comment about Hansen was odd, too. There was nothing in his reference to support what he wrote.

RR quotes: is that the EQUILIBRIUM warming is proportional to the radiative forcing

Yes. But you are not using the EQUILIBRIUM warming, which will be greater than 0.8. You are using the TRANSIENT warming to calculate the EQUILIBRIUM sensitivity.

Repeatedly highlighting the word "EQUILIBRIUM" in a whole bunch of quotes does not make your use of TRANSIENT temperature change magically become EQUILIBRIUM temperature change.

Everyone else here understands this. So, either you're substantially dimmer than the rest of the crowd, or you're being deliberately deceptive.

As for the fact that the earth system generally doesn't settle into an actual equilibrium state ... so what? All that means is that we'll never be able to actually use your equation to precisely calculate ECS, because we'll never precisely know the equilibrium temperature response. Right now we know dT is something greater than 0.8, but we don't know how *much* greater.

"Equilibrium climate sensitivity is likely to be in the range 2°C to 4.5°C with a most likely value of about 3°C, based upon multiple observational and modelling constraints. It is very unlikely to be less than 1.5°C."

Note please that the IPCC ECS is 3C. That includes all the feedbacks, and is at equilibrium.

OK? Can we agree so far? The IPCC has said the ECS is 3C.

So now we have a very simple test. Using the 0.8 figure if the ECS comes out at 3C then all the feedbacks have been accounted for and we are at equilibrium.

In today's world of competitive grant applications one has to "big-note" one's research in order to give the best chance of securing funding. It should be noted that CERN have a great track record of securing funding in the region of the multi-millions (e.g. LHC, CLOUD etc.) and thus demonstrate this "big-noting" is a successful strategy. Thus we should not criticise here but rather take note of the techniques demonstrated by Kirby.

Sou: “Jasper claims that the "present range of uncertainty is simply too large to be confident of how best to respond". I disagree. We already know enough that at the very least, we need to cut emissions of CO2.”

Jasper didn’t say anything about NOT reducing emissions. He said lack of certainty means we don’t know how BEST to respond. It isn’t a simple black and white choice between reducing emissions and not reducing emissions. It’s about remediation vs adaptation, how much we invest in which technologies, and over what timespan.

First part is quite correct (for many reasons other than climate change), but second part is somewhere between hopelessly simplistic to utterly wrong. Renewables have next to no chance of significantly reducing fossil fuel burning. Do the math. That this is a fact has nothing to do with climate science, it is based on economics and engineering. Overall the issue of applying technology to reduce emissions in mired in a very complex mish-mash of politics and various academic principles, some of which have nothing to do with science. The problem is very difficult to address, and that is the reason uncertainty plays havoc with policy.

And this, in my opinion, is the big problem with the climate change debate. Too many people think the issue is only about agreeing on climate science. It isn’t.

So you are saying it's hopeless. That we will simply use up all non-renewables in the next couple of hundred years and then come to a full stop and peter out.

I don't agree. I'm not saying it will be easy, but there are a lot of studies that show we can shift to economies that are sustainable in the longer term from an energy perspective, should we choose longevity for the human species rather than give up and spiral into a rapid demise.

Far from it. I am extremely optimistic that we CAN have a future minus fossil fuels and where renewables play a suitable supplemental role (in keeping with their limitation of intermittency). We just need to get the policy right.

Sou: ”That we will simply use up all non-renewables in the next couple of hundred years and then come to a full stop and peter out. “

That isn’t the problem. Non-renewables will not run out in a few hundred years, we have thousands of years of available nuclear fission (uranium and thorium). Have you seen Pandora’s Promise? Very compelling and technically accurate too. And after that we have the prospect of nuclear fusion, which is fueled by water. And maybe other forms of energy production that we have not yet invented, which are fueled efficiently by abundant resources.

Sou: “there are a lot of studies that show we can shift to economies that are sustainable in the longer term from an energy perspective”

I have seen many such studies too, and in my experience they are typically driven by vested interests, and rarely take into account the issues of stability and availability (reliability), the extreme cost of deploying the technology in the absence of suitably affordable energy storage technologies through over-capacity, or rely on uneconomical idle stand-by generation systems like bio-fuelled turbines (eg Diesendorf). For example the BZE plan, which was thoroughly debunked at BraveNewClimate by qualified engineers who work in the field. Jacobson and Delucchi (2007) is debunked here, where it is described as “utterly egregious and deceptive”. In a nutshell, such ”studies” are nonsense and based on pseudo engineering, green ideology and wishful thinking.

Intermittent renewables simply do not scale beyond supplemental use at about 20% capacity. It’s a fact of engineering and economics with current technology. It doesn’t matter how compelling climate science is, the urgency of action, the solution has to be technically AND economically viable or it simply won’t work. And right now renewables alone are nowhere near able to reduce fossil fuel use enough to remediate global CO2 emissions.

The problem is too many people believe in nonsense instead of the experts? Apparently people want this is be black and white and simple to resolve with an ideal sustainable technology stack, when it is actually really complex and requires compromise and time. This compounds on the lack of scientific certainty in climate projection (which Jasper Kirkby is working on) and is playing havoc with the setting of good policy.

Oh, so it was nothing more than a nitpick over my use of the word 'renewables' rather than 'not fossil fuel'. You could have just said "and nuclear" in your first comment and saved an awful lot of comment space.

Sou, not everyone is enlightened when it comes to the potential need for nuclear power. And Steve and Harry were looking for some evidence for my statement : "Renewables have next to no chance of significantly reducing fossil fuel burning. Do the math.". I felt compelled to explain properly.

Anonymous (why anonymous) claims " the BZE plan, which was thoroughly debunked at BraveNewClimate by qualified engineers who work in the field."

That is not true.

It was attacked by climate denier nutter (literally - he is an angry fanatic who is regularly banned and then reinstated at BNC) Peter Lang and then by counter culture guru Ted Trainer from the Simplicity Institute.

Read this post from John Quiggin for some background on this pair (see fn2)http://johnquiggin.com/2014/10/12/a-simple-route-to-climate-disaster/

As well as BZE's plan, there is a 100% renewable plan from the Australian Energy Market Operator (AEMO) the group responsible for managing our electricity market and for strategic planning.https://theconversation.com/zero-emissions-power-is-possible-and-we-know-what-it-will-cost-13866

And the UNSW plan from Mark Diesendorf et alhttps://theconversation.com/renewable-energy-is-ready-to-supply-all-of-australias-electricity-29200

Mike the AEMO plan is absrdly expensive, so is the UNSW plan, and relies on 30% biofuel standby which is not proven and big big drawbacks. Are you an expert in energy generation and engineering? I am. You need to listen to the experts instead of deciding what suits your ideology like the NFIs at WUWT.

IIRC Kirkby was originally far more outspoken about his hopes that the CLOUD results would cancel concerns about rising CO2, until maybe two years ago when the director of CERN told him in no uncertain terms to put a sock in it.

This new fangled invention the 'motor car' will never replace our beasts of burden for transport. We do not have any way of feeding the needs and maintenance of these machines everywhere. It is obvious that motive power on farms will never be replaced by these machines. All the needs of the horses and bullocks can be met on farm.These machines are hopelessly inefficient and costly. They will never replace what we have now. Their source of power is a limited resource in the ground that was laid down millions of years ago!Exploiting these reserves needed to fuel the machines is costly and polluting. At least the waste of our beasts of burden are plant food! Bert

These new sources of energy are nowhere near as reliable as coal or nuclear. What a pathetic answer is renewable energy as it is intermittent and sporadic.This is the absolute rubbish that gets repeated as nauseum.Nuclear energy if based on U235 as a fuel will last for about forty years at current use of coal. Thorium reactors are just a pipedream just like nuclear fusion reactors.The only viable fusion reactor is above our heads. It is called the Sun.We have to learn how to make use of renewable energy. There is no choice, starve to death due to desertification of our food bowls and keep sacrificing our young to the great gods of our idiocy.It is up to all of us to work this out. I do not give a damn about myself. I am old and closer to death than birth. I have stopped buying green bananas. Bert

I don't want to get into a lengthy discussion of nuclear vs renewable but agree with you, Bert, that nuclear is not a long term solution. Look at how France had to shut down some of its reactors during the heat waves of 2003 and 2006.

More on this here:http://www.theguardian.com/environment/2006/jul/30/energy.weather

Imagine the difficulty of finding sites in Australia that had ample water for cooling, were unlikely to be shut down during the angrier summers to come, weren't under threat of floods, weren't going to be encroached by rising seas and were close enough to centres of large population that the cost of distribution wasn't prohibitive. Then imagine people being willing to cough up the funds to build them Then imagine people willing to live near such sites. Heck, some people complain about wind turbines. Imagine how they would complain about a nuclear power plant.

I'm aware that pebble bed reactors are considered an improvement, but from what I've read they aren't nearly as efficient and are much more expensive to build - though that could change I suppose.

http://www.dvice.com/archives/2011/03/how_to_make_a_n.php

I don't like nuclear power but I like fossil fuel burning even less. Nuclear is very costly, from a security point of view isn't on par with a more distributed system (like wind/solar), is riskier from a safety viewpoint, and relies on a non-renewable resource. I reluctantly accept that it may be needed in some parts of the world, as a stopgap as the world shifts to renewable energy.

Sou I went to the Synchrotron at Grenoble to do some data collection. Part of the complex was a dedicated nuclear reactor. It had heavy duty guards. These blokes were very smart they treated me with complete open an honest respect. They were the equivalent of our SAS. I came back one night very pissed from drinking at a bar called 'le Hades' . It was the same decor as it had three hundred years ago. The bar was a slab of timber that had been there since its inception.When I fronted the entrance of the Synchrotron very pissed the guards took one look at my face and waved me through. They knew where I had been and what I had done. Bert

Bert from Eltham, your motor car vs horse analogy works just the same for all forms of new technology, whether it be renewables, nuclear fission or nuclear fusion. The difference is that nuclear fission has already solved all of the problems that you and Sou are worried about, but as yet renewables “we need to learn how to make use of”.

There is enough uranium to last millennia - see fast breeders Thorium reactors were around even before the current conventional uranium reactor.Nuclear power is cheaper than the equivalent solar/wind + idle standby gas backup (the latter emits more CO2, and is arguably more dangerous)Fission reactors can be air or molten salt cooled There are innumerable places in regional Australia that are like the French begging for the business generated by a nuclear plant, we haven’t even tested this yet. Are the French inherently smarter than Australians?

Sou: “… as the world shifts to renewable energy” .

Why do you assume that the world will ultimately move to renewables? There may be other, better long-term solutions. I regret to say this assumption that for some reason we are compelled to pursue expensive and limited intermittent energy sources (rather than cleaner, safer, cheaper, reliable solutions) is currently preventing us from reducing greenhouse emissions, and confounding the implementation of viable climate change policy. How long will this continue?

>nuclear fission has already solved all of the problems that you and Sou are worried about

No it hasn't. It's hugely expensive, can't be implemented without government funding, is opposed by most people living in the vicinity (NIMBY). It poses security risks much greater than any other form of power production. It is cumbersome, not ideally suited to a very hot world, relies on a non-renewable resource, is dependent on costly distribution networks that are themselves unreliable in a hotter world, and the mining of the raw material and upchain use poses a danger for centuries etc etc. It's a stop gap at best.

Anonymous, we get you're a nuclear/uranium advocate. The world is big enough for you and people who don't particularly want to have to rely on it. You don't need to go on and on about it. if you'd made it clear from the start what you were talking about, your comment could have just stood as one of various opinions on the subject. Now you find yourself trying to defend your position. Go take your argument to Barry Brooks' blog or somewhere, where you'll find lots of people agreeing with you, whatever you are arguing.

What I'd read (and then written) about pebble bed reactors is that they should be far safer and far more efficient at converting fuel into electricity. And that they're totally experimental and have never been built at scale. I say written because I helped write a grant (which we didn't win) to build software to simulate them.

If nuclear was as promising as some claim, they'd be being built. None of these are ready for commercial operation, some've had huge cost over-runs. By the time any are built (2030s at the earliest, if ever), there'll be a lot more renewables in operation at current growth rates:

South Africa:http://www.nature.com/news/2010/100223/full/4631008b.html

You know if Anonymous wants to think that renewables don't scale and it's all vested interests, he's fine to think so. I will personally keep investing in renewables and electric vehicles...I'm doing fine thank you :) Something to read is a simple Wikipedia post on Germany's efforts in renewables: http://en.wikipedia.org/wiki/Renewable_energy_in_Germany

Germany is now at 30%. Hmmm, sorry, don't see the scaling issue.

Then there's this: http://www.bloomberg.com/news/2013-02-06/australia-wind-energy-cheaper-than-coal-natural-gas-bnef-says.htmlBloomberg says that wind is cheaper energy than coal or gas in Australia. The main thing to understand here, though, is that it's still early for wind and the innovation curve is much steeper than coal or gas.

Sou, none of the problems you have raised are significant impediments to nuclear power. The experts have repeatedly debunked these concerns, yet the anti-nuclear myths keep getting repeated over and over by pseudo engineers and ideologues. Such foolish politics and general ignorance remains the only impediment to nuclear power.

Nuclear is only expensive in terms of total cost for a single plant. More importantly, it is cheaper than all other forms of production on a per GWh delivered basis , except coal and supplemental wind. This includes the cost of waste disposal and plant decomm. Note to Joe – nuclear is cheaper than wind when you consider availability/reliability, i.e. add distributed over capacity or idle standby generation.

NIMBYs may be a problem in Australia, or not, we don’t know yet - it certainly isn’t a problem in many overseas deployments. Intermittent solar and wind also relies on distribution networks same as nuclear, yet distribution of centralized power production is still the most cost effective way of delivering power to industry and commerce (80% of the energy market). Long-term waste management is an engineering problem that was solved decades ago.

Nuclear plants are being built , just not the newer designs yet because it is still way cheaper to build the Gen 3+ designs. China and France have solid plans to build fast breeders starting in 2030. Others (US, Canada, India, UK, Sweden …) will follow. Australia’s first reactor may be a FBR.

Although I argue strongly for nuclear, I am more concerned that most climate change advocates only see renewables as a suitable solution. I am strongly opposed to the idea that renewables are the fundamental answer to resolving climate change, because they have limitations and pursuing them exclusively is stopping us from implementing aggressive decarbonizing policies.

Finally, Joe, renewable capacity in Germany is indeed approaching 30%, and has seriously stagnated – it certainly cannot economically scale beyond current capacity. Germany is building new coal plants to help provide the remaining 70% of required power. If they used nuclear instead, they would be reducing their emissions footprint.

Also, Wikipedia doesn't share your view that Denmark is hitting limits. Wind power alone has gone from 29.9% of power used inn 2012 to 32.7% in 2013 to an estimated 38.8% in 2014:http://en.wikipedia.org/wiki/Wind_power_in_Denmark

Anon: "Nuclear is only expensive in terms of total cost for a single plant"

Solar, wind and hydro are even cheaper than nuclear if you exclude the construction cost. But nobody reasonable excludes construction and decommissioning cost for something that has a limited lifetime.

Anon, you really come off as quite silly when you condescend with "so you are learning..." "perhaps have a read..." after making numerous errors. Just admit that you're a biased proponent for nuclear power and you make up stuff on the fly. I'm quite aware of issues with intermittent power and how they're solved. The fact that renewable energy continues to grow at scale is because of those solutions. It's the reason why my investments have done so well :)

Numerobis, I think you misunderstand. I am not excluding any costs, I am merely pointing out that the correct comparison of the price of energy is not the total cost of a single plant of unspecified capacity (as Sou suggested), but the price/kWh of the electricity when all costs are included. In that case nuclear is relatively inexpensive, see http://www.world-nuclear.org/info/Economic-Aspects/Economics-of-Nuclear-Power/

Joe, I have actually not made any errors. But you have. You think that the scaling of wind power has relevance to the success of wind power as an investment - it doesn’t, at least not yet. Wind power companies currently make good money by selling equipment and projects, including a capital cost of construction (amortised over the plant life), operating costs and a 10-20 year annuity based maintenance contract which ensures long term profitability of the company. Your argument that wind power can scale indefinitely because your investments are currently successful, is just silly.

Anon, you just keep making stuff up. If wind power weren't growing as an industry, (some of) my investments would dry up (I invest in more than just wind). Businesses don't grow and make good money when the greater industry "stagnates" - and stock prices are correlated to discounted future cashflows. And there is more than just wind. Iceland gets 99% of their power from geothermal. New Zealand gets 75% of their power from renewables, of which the majority is hydro. You're so stuck in ideology, you can't see forest from trees.

But lets get back to your errors, which you claim you haven't made:German renewables have stagnated - false, still growing, even into 2014Danish renewables has hit capacity limits- false, still growing, even into 2014Your link below to Eric Rosenbloom's page has numerous errors. The obvious one was the claim that wind hasn't affected fossil fuel use and CO2 emissions in Denmark...I put up a link which showed it false. There are other errors pointed out by others, but I'll stick to the ones I've found. My greater point about investments, which you missed, is that you typically research heavily before you invest (at least I do). Thus, it was easy to see where you were making stuff up or exaggerating points.

We hold this truth to be self-evident: that everyone (sans a few vested interests) stands to benefit from the creation of the most expansive and effective renewable power network practically possible.

If you're trying to undermine this on behalf of the fossil fuel dinosaurs, you're a wrecker. And if you're trying to undermine this on behalf of your pet Byzantine high technology, you're a wrecker, too. (Sadly this latter is a very common practice.)

South Australia has already bowled over many of the naysayers alarmist claims; let's all get going and keep going!...

We hold this truth to be self-evident: that everyone (sans a few vested interests) stands to benefit from reducing the use of fossil fuels in power production.

If you undermine this by insisting on expensive and intermittent renewables (as opposed to other more reliable low emissions technology) because you are unwittingly beholden to vested commercial interests in the (renewable) energy industry, then you are a wrecker.

We cannot “keep going” building supplemental wind power systems, it isn’t technically nor economically viable. You clearly don’t understand why this is the case, because you are not QUALIFIED as an engineer. Please defer to expertise in this matter, otherwise you are a wrecker.

Dhogaza, your facile comment indicates that you are not an engineer, you do not understand the limitation of supplemental energy production in large-scale deployment. Suggest you educate yourself. Try this: http://www.aweo.org/problemwithwind.html

“As in Denmark and Germany, the electricity from those towers -- no matter how many -- would be too variable to provide the predictable supply that the grid demands. They would have no effect on established electricity generation, energy use, or continuing pollution.”

Anonymous is a QUALIFIED engineer, eh? Well, if you say so... but, of course other QUALIFIED people, including ENGINEERS, don't agree with you, so go figure!

Your BOMBASTIC argument from AUTHORITY technique - which seems to be a FEATURE rather than a BUG of pro-Nuke advocacy - ain't likely to win you many FRIENDS in this, or any other, debate, either, so, by all means, CONTINUE...

Sheesh, I missed that one, Marco. Don't tell me we've been invaded by an anti-wind alarmist! I thought the comments were getting rattier (unsubstantiated wild claims) by the minute, but was busy on other stuff and didn't check.

Yes I am a qualified engineer, and I am like Sou very busy, and do not spend my life collecting and researching online references. I am interested in seeing good counter references for the assertion (that appears to be commonly accepted here without evidence) that supplemental intermittent renewable energy (wind and solar power) can cost effectively exceed 20% of capacity. If anyone can make the case for scalability of intermittent power sources, then I am interested, though I should say I think this is a wild and ratty assertion.

Anyone?

Otherwise I believe that I have accurately conveyed the facts of the matter, and demonstrated the reason why baseload energy sources like nuclear power are important to reducing CO2 emissions.

Yup Sou. I invest in renewables so became suspicious of anon's "facts" based on what I know. If they were true, I wouldn't be making money on my investments (I don't invest on ideology). Sure enough, as I double-checked, they were false.

Single wind, solar, etc. plants have serious problems with intermittency, but as they are scaled up and interconnected over geographic extent in a shared grid the reliable baseline percentage rises accordingly, as per Archer et al 2007, with accompanying reductions in transmission capacity requirements. The increase is less than linear, but apparently not bounded.

Also, an EU analysis finds that onshore wind is the cheapest energy solution (€105 per MW/h) if you include add-on costs such as air quality, health impacts, and climate change. Nuclear, offshore wind, and solar are the the next most expensive around €125, gas €164, coal €233 per MW/h.

Many of the arguments about intermittency seem to come down to considering a single renewable plant in isolation, and ignoring social costs - and that's unrealistic.

What a fuss about Eric Rosenbloom. What exactly is he saying that you don’t agree with, and where are your counter references?

Reading the links offered, the proof for scalability being presented appears to be based on the long-term promises of politicians (eg Jay Weatherill and nameless German counterparts) who will not be around in 2050 when their crazy promises are supposed to reach fruition. Plans for >20% wind power capacity rely on their state/country being able to import power from baseload or idle stand-by generators outside their region. They in no way counter the fact that supplemental power has a cost effective limit of around 20% total capacity, and that 80% baseload nuclear/coal/CCGT and/or expensive idle standby gas or hydro systems are needed for stable electricity supply.

http://en.wikipedia.org/wiki/Wind_power_in_Denmark claims a capacity of windpower in Denmark of 38-41%, however this is misleading since the Danes rely on importing baseload power from neighbouring countries, when the wind isn’t blowing, and this capacity is not included in the % figure. And be aware, Denmark has the highest household electricity prices in the world, probably because they have exceeded the cost effective capacity of wind power.

In answer to KR, intermittency resolution through geographic distribution requires expensive power networking, which as Sou has pointed out, is a risk in a hotter world. The network costs makes the wind power unaffordable relative to baseload sources. The EU analysis that concludes with the claim that wind is “the cheapest energy solution” is not an apples vs apples comparison, as it is based on single plant, supplemental electricity pricing and does not include the cost of idle standby backup or power distribution costs.

Anonymous, the "fuss about Eric Rosenbloom" is the credibility of your references.

The baseload power that Denmark imports is limited, and in part is hydropower from Norway...which is partly powered by wind power from Denmark!

And no, Denmark does not have the highest household electricity prices in the world because of wind power. Electricity costs are actually one of the lowest in Europe:http://epp.eurostat.ec.europa.eu/statistics_explained/images/8/89/Electricity_prices_for_household_consumers%2C_first_half_2013_%281%29_%28EUR_per_kWh%29_YB14.pngDenmark just has one of the highest levies to reduce energy use, and also a very high VAT.

I am NOT opposed to renewables, they have a big part to play, up to a point. I am opposed to those who think renewables are the one and only answer to climate change policy and reject other technologies like nuclear. Such thinking is just plain wrong, the evidence is there I have tried to explain it, for some reason people refuse to believe it. It makes me really sad, as this thick headed behavior is preventing us from deploying policies that will actually resolve this issue.

Oh, I reckon we're done. Given your performance above, oh anonymous ENGINEER, I don't think anyone reading this is likely to rate you particularly highly in the credibility stakes.

And your comprehension skills are on par - that's 50% for SA by 2025, because renewables already account for 31.4% of the state's production - i.e. 11.4% more than you claim is even technically feasible!

'Pompous ass' is about right. You are apparently your own - and your cause's - worst enemy...

SA can get more than 20% capacity because they buy baseload power (brown coal fired) from Victoria. Some places can get more that 20% capacity, others less than 20% but overall the maximum is about 20%. I have tried to explain this, but for some reason you just don’t understand it. Try this:

“On a full-grid perspective, Intermittent energy such as wind and solar require 20 to 30 percent energy backup for short falls when these intermittent sources provide up to 20% of the grid’s energy. Most of that backup doesn’t have to be built as it will come from neighbouring jurisdictions, passive hydro and existing natural gas peaking plants."

A recent US NREL study examined use of up to 35% renewable power into the Western US grid. Note - this is >20%.

Key Findings (some emphasis added)

* The integration of 35% wind and solar energy into the electric power system will not require extensive infrastructure if changes are made to operational practices.

* Operating costs increase by 2–5% on average for fossil fueled plants when high penetrations of variable renewables are added to the electric grid.

* Wind and solar energy displace fossil fuels. A 35% penetration of solar and wind power would reduce fuel costs by 40% and carbon emissions by 25%–45%—the rough equivalent of taking 22–36 million cars off the road—compared to today's system. [Fuel costs reduce by $7B, while maintenance costs for fossil fuel cycling increase by $35-160M. Note the difference in scale.]

* Increasing the size of the geographic area over which the wind and solar resources are drawn substantially reduces variability.

"The central conclusion of the analysis is that renewable electricity generation from technologies that are commercially available today, in combination with a more flexible electric system, is more than adequate to supply 80% of total U.S. electricity generation in 2050 while meeting electricity demand on an hourly basis in every region of the United States. "

One (not so minor) point to make regarding Anon's objections: quoting studies that examined up to 20% renewable penetration doesn't mean >20% is impossible - merely that such levels were not studied in that particular work.

Anon, your article was way out of date and focussed on individual cases & lobbyists (eg. "Country Guardian was founded in 1992 to oppose wind farms in unspoiled rural areas of the U.K. "). It is very easy to find debunking material - take a look at this for example. There is a whole section on Denmark [PS Sou could we have some html guidance for reference somewhere? I have to teach myself each time. Is it poss. to embed images easily?]

Thanks Sou, I nearly didn't bother as it said that 'html' couldn't be used, so I stripped it out, but perhaps should have replaced with www?. The second link to Denmark specifically is here http://www.wind-works.org/cms/index.php?id=102

Hi Katy, I had a good look at the Wind-works site, and it appears that Paul Gipes has a vested interest. He is a shill for the wind energy industry, and is funded by private grants, books sales and lectures. He writes and sells books about wind energy, and the web site is for promoting those books. He apparently has no academic qualifications.

Having said that most of what he writes is fairly accurate. And it does not in any way contradict the points I have made here about intermittency and its limiting of scale. The site directs to this link http://barnardonwind.com/2013/02/24/how-much-backup-does-a-wind-farm-require-how-does-that-compare-to-conventional-generation/ which actually confirms my argument:

“On a full-grid perspective, Intermittent energy such as wind and solar require 20 to 30 percent energy backup for short falls when these intermittent sources provide up to 20% of the grid’s energy. Most of that backup doesn’t have to be built as it will come from neighbouring jurisdictions, passive hydro and existing natural gas peaking plants."

Again, you err as it does not support your argument about "limiting of scale" unless you mean something completely different by scale limits than I'm used to. Scale limits mean that wind can't be in the same order of magnitude of scale as other energy sources. The fact that it already is in a number of countries makes that view false. If by limits you mean that it can't keep growing once it hits the same order of magnitude as other energy sources, you're wrong again because it's still growing in Denmark and Germany, for example. If by scaling limits, you mean that you still need 20% capacity from something else for shortfalls, well we may agree but that's barely a limit. And again, renewables are not limited to wind. Even the article you link to mentions passive hydro as a possibility for those shortfalls. IOW, it could be 100% renewables. New Zealand is 75% (wind is only 5% in NZ, but the fastest growing).

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All you need to know about WUWT

WUWT insider Willis Eschenbach tells you all you need to know about Anthony Watts and his blog, WattsUpWithThat (WUWT). As part of his scathing commentary, Wondering Willis accuses Anthony Watts of being clueless about the blog articles he posts. To paraphrase:

Even if Anthony had a year to analyze and dissect each piece...(he couldn't tell if it would)... stand the harsh light of public exposure.

Definition of Denier (Oxford): A person who denies something, especially someone who refuses to admit the truth of a concept or proposition that is supported by the majority of scientific or historical evidence.
‘a prominent denier of global warming’
‘a climate change denier’

Alternative definition: A former French coin, equal to one twelfth of a Sou, which was withdrawn in the 19th century. Oxford. (The denier has since resurfaced with reduced value.)